package com.cinyi.cyds.base.html;

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.Writer;
import java.util.Locale;
import java.util.Map;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.web.servlet.support.RequestContextUtils;
import org.springframework.web.servlet.view.freemarker.FreeMarkerView;
import freemarker.template.SimpleHash;
import freemarker.template.Template;
import freemarker.template.TemplateException;

public class ExFreeMarkerView extends FreeMarkerView {
	@Override
	protected void doRender(Map<String, Object> model,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {
		exposeModelAsRequestAttributes(model, request);
		SimpleHash fmModel = buildTemplateModel(model, request, response);
		if (logger.isDebugEnabled()) {
			logger.debug("Rendering FreeMarker template [" + getUrl()
					+ "] in FreeMarkerView '" + getBeanName() + "'");
		}
		Locale locale = RequestContextUtils.getLocale(request);
		/**
		 * 在这里我们默认生成静态文件,当ModelAndView有指定STATIC_HTML = false时,就不会输出HTML文件*
		 * 例如：ModelAndView modelAndView = new ModelAndView("htmlTest");*
		 * modelAndView.addObject("STATICHTML", false);
		 */
		if (Boolean.FALSE.equals(model.get("STATIC_HTML"))) {
			processTemplate(getTemplate(locale), fmModel, response);
		} else {
			createHTML(getTemplate(locale), fmModel, request, response);
		}
	}

	public void createHTML(Template template, SimpleHash model,
			HttpServletRequest request, HttpServletResponse response)
			throws IOException, TemplateException, ServletException {
		/** 站点根目录的绝对路径 **/
		String basePath = request.getSession().getServletContext()
				.getRealPath("/");
		String requestHTML = this.getRequestHTML(request);
		/** 静态页面绝对路径 **/
		String htmlPath = basePath + requestHTML;
		File htmlFile = new File(htmlPath);
		if (!htmlFile.getParentFile().exists()) {
			htmlFile.getParentFile().mkdirs();
		}
		/*** 如果静态页面已经存在,就不再创建静态页面. */
		if (!htmlFile.exists()) {
			htmlFile.createNewFile();
			Writer out = new BufferedWriter(new OutputStreamWriter(
					new FileOutputStream(htmlFile), "UTF-8"));
			/** 处理模版 **/
			template.process(model, out);
			out.flush();
			out.close();
		}
		/* 将请求转发到生成的htm文件 */
		request.getRequestDispatcher(requestHTML).forward(request, response);
	}

	/*** 计算要生成的静态文件相对路径. */
	private String getRequestHTML(HttpServletRequest request) {
		/** web应用名称,部署在ROOT目录时为空 **/
		String contextPath = request.getContextPath();
		/** web应用/目录/文件.do **/
		String requestURI = request.getRequestURI();
		/** basePath里面已经有了web应用名称，所以直接把它replace掉，以免重复 **/
		requestURI = requestURI.replaceFirst(contextPath, "");
		/** 将.do改为.htm,稍后将请求转发到此htm文件 **/
		requestURI = requestURI.substring(0, requestURI.indexOf(".")) + ".htm";
		return requestURI;
	}
}